Role of DNA repair genes XRCC3 and XRCC1 in predisposition to type 2 diabetes mellitus and diabetic nephropathy / Papel de los genes de reparación del ADN XRCC3 y XRCC1 en la predisposición a la diabetes mellitus de tipo 2 y a la nefropatía diabética

Introduction: Increasing number of experimental and clinical studies suggest a strong relationship between hyperglycemia, oxidative stress, DNA damage and diabetic nephropathy (DN). Also, epidemiologic studies remark an enhanced risk of cancer with type 2 diabetes. This research aims to assess whether the X-ray cross complementing group 3 (XRCC3) gene T241M polymorphism (rs861539) and X-ray cross complementing group 1 (XRCC1) gene A399G polymorphism (rs25487) are related with predisposition to type 2 diabetes mellitus (T2DM) and to diabetic nephropathy in Turkish population. Materials and methods: Polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) was performed to identify the distribution of genotypes and frequency of alleles of T241M polymorphism of the XRCC3 gene (XRCC3 T241M) and A399G polymorphism of the XRCC1 gene (XRCC1 A399G). The study population included 238 subjects residing in Istanbul, Turkey; 116 with T2DM, 50 with DN and 72 with normal glucose metabolism. Results and conclusion: Polymorphic Gln allele of XRCC1 gene was significantly related with T2DM and DN (OR 3.09, 95% CI 1.14-8.40 and OR 3.29 95% CI 1.23-8.80, respectively) however, there was no statistical association of XRCC3 T241M with T2DM or DN. The results of this study suggest that XRCC1 399Gln polymorphism is related with an increased susceptibility to T2DM and DN in the studied Turkish population

Introducción: Un número creciente de estudios experimentales y clínicos sugiere una sólida relación entre hiperglucemia, estrés oxidativo, daño en el ADN y nefropatía diabética (ND). Además, los estudios epidemiológicos advierten mayor riesgo de cáncer con diabetes de tipo 2. Esta investigación tiene como objetivo evaluar si el polimorfismo del gen T241M del grupo 3 (XRCC3) complementario cruzado de rayos X (rs861539) y el polimorfismo del gen A399G del grupo 1 (XRCC1) complementario cruzado de rayos X (rs25487) están relacionados con la predisposición a la diabetes mellitus de tipo 2 (DM2) y a la nefropatía diabética en la población turca. Materiales y métodos: Se realizó un polimorfismo de longitud de fragmento de restricción basado en la reacción en cadena de la polimerasa (PCR-RFLP) para identificar la distribución de genotipos y la frecuencia de los alelos del polimorfismo T241M del gen XRCC3 (XRCC3 T241M) y el polimorfismo A399G del gen XRCC1(XRCC1 A399G). La población de estudio incluyó a 238 individuos que residían en Estambul, Turquía; 116 de ellos con DM2, 50 con ND y 72 con metabolismo de la glucosa normal. Resultados y conclusión: El alelo Gln polimórfico del gen XRCC1 se relacionó de manera importante con DM2 y ND (OR: 3,09; IC95%: 1,14-8,40 y OR: 3,29; IC95%:1,23-8,80, respectivamente). Sin embargo, no hubo asociación estadística de XRCC3 T241M con DM2 o ND. Los resultados de este estudio sugieren que el polimorfismo XRCC1 399Gln está relacionado con un aumento de la susceptibilidad a la DM2 y a la ND en la población turca estudiada

Role of DNA repair genes XRCC3 and XRCC1 in predisposition to type 2 diabetes mellitus and diabetic nephropathy.

INTRODUCTION: Increasing number of experimental and clinical studies suggest a strong relationship between hyperglycemia, oxidative stress, DNA damage and diabetic nephropathy (DN). Also, epidemiologic studies remark an enhanced risk of cancer with type 2 diabetes. This research aims to assess whether the X-ray cross complementing group 3 (XRCC3) gene T241M polymorphism (rs861539) and X-ray cross complementing group 1 (XRCC1) gene A399G polymorphism (rs25487) are related with predisposition to type 2 diabetes mellitus (T2DM) and to diabetic nephropathy in Turkish population. MATERIALS AND METHODS: Polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) was performed to identify the distribution of genotypes and frequency of alleles of T241M polymorphism of the XRCC3 gene (XRCC3 T241M) and A399G polymorphism of the XRCC1 gene (XRCC1 A399G). The study population included 238 subjects residing in Istanbul, Turkey; 116 with T2DM, 50 with DN and 72 with normal glucose metabolism. RESULTS AND CONCLUSION: Polymorphic Gln allele of XRCC1 gene was significantly related with T2DM and DN (OR 3.09, 95% CI 1.14-8.40 and OR 3.29 95% CI 1.23-8.80, respectively) however, there was no statistical association of XRCC3 T241M with T2DM or DN. The results of this study suggest that XRCC1 399Gln polymorphism is related with an increased susceptibility to T2DM and DN in the studied Turkish population.

Investigation of genotoxicity risk and DNA repair capacity in breast cancer patients using anastrozole.

OBJECTIVE: Breast cancer is the most common cancer in women worldwide and the incidence increases in postmenopausal women. Anastrozole is a non-steroidal (type II), third-generation aromatase inhibitor (AI) that is used in the treatment of postmenopausal estrogen-related breast cancer. Several studies have been conducted to assess the efficacy, safety, and superiority of AIs to tamoxifen; however, a literature search did not reveal a study that investigated the genotoxic potential of AIs. The aim of this study was to investigate the possible DNA damage risk profile and individual DNA repair capacity of patients using anastrozole with the modified alkaline comet assay in order to contribute to public health and health economics. METHODS: Women diagnosed with breast cancer after menopause comprised the study group. Six patients who had taken anastrozole for at least 6 months were retrospectively enrolled, and 12 patients who had not yet received treatment were prospectively enrolled as a control group. Peripheral blood lymphocytes were used to measure oxidized DNA damage using formamidopyrimidine DNA-glycosylase (FPG) and endonuclease III (endo III) in a modified comet assay. Individual DNA repair capacity was evaluated with the comet assay after a hydrogen peroxide (H2O2) challenge to examine the difference in DNA damage susceptibility. RESULTS: Analysis of DNA damage, oxidative base damage, susceptibility to DNA damage, and repair capacity revealed no significant difference between the control group and the patients taking anastrozole (p>0.05). Susceptibility to H2O2 damage was observed to increase with age (p<0.05). CONCLUSION: According to the results obtained in this study, anastrozole did not contribute to oxidative DNA damage. An H2O2 challenge with the comet assay is useful to evaluate circumstances of increased vulnerability to damage, such as aging and cancer.